Fixed the visibility state (the checkboxes in the Window menu) to represent panels that are visible and active in the workspace. Should now also properly close panel when clicking on an item that is currently visible.

Fix issue that could cause the Event Panel to become blank (mostly affected FireFox users)
Fix issue having to right click a vehicle in the Vehicle Panel two times before the menu would appear (mostly affected FireFox users)

Changes made to settings in Map Panel menu (Marker Attributes, Vehicle Marker Settings etc) is now saved automatically to the workspace.